over the past six moks, the number of civilians killed in this civil war has been climbing steeply. one of the organizations keeping track is the syrian observer for human rights and its spokesman is mataz suheil. how many were you seeing a year ago. >> a year ago, we would see 60 people killed. yesterday was 200. the day before 100. the day bench that 210. >> reporter: driving that escalation in part, rebel fighters who have taken over civilian neighborhoods, turning them into battle zones. another factor it's syrian military is attacking more and more often from the air. when cbs news visited the damascus suburbs in november, sarah, a 21-year-old activist, showed us the damage done by a missile fired from a russian-made mig fighter plane. is that the worst, seeing a fighter plane overhead? >> yeah, the mig is the worst thing have ever happened to us. we can't have any safe place to hide. >> we see this as an attempt to either force migration or the depopulating entire zones. >> reporter: it's working, too. >> it is. >> reporter: half a million people have been sent fleeing already